Infections with viruses, including flaviviruses, such as West Nile flavivirus, Dengue flavivirus, Japanese encephalitis flavivirus, Langat flavivirus, Kunjin flavivirus, Murray Valley encephalitis flavivirus, Tick-borne flavivirus and Yellow fever flavivirus, can result in serious disease and, possibly death. Mosquitos and ticks transmit many of the flaviviruses. For example, severe symptoms of West Nile virus infection include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness, meningoencephalitis and paralysis. These symptoms may last several weeks, and neurological effects may be permanent. In cases with milder symptoms (e.g., fever, headache, and body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach and back), certain symptoms, such as fever and aches, can pass on their own. In more severe cases, people usually require hospitalization for treatment, such as administration of intravenous fluids and assistance with breathing.
Methods to prevent flavivirus infection include compositions of live attenuated and inactivated virus. However, such compositions may be less than optimally immunogenic, may result in unknown hazards if improperly prepared and may have adverse side effects. There is a need to develop new compositions and methods to prevent flavivirus infection.